Previous research favours the idea that modern humans spread worldwide from Africa. For instance, autosomal diversity falls as geographical distance from Africa rises, and, through autosomal diversity, an area of origin for this worldwide expansion is indicated to be within Africa entirely. Declines are also known to happen for mitochondrial, X-chromosomal, and Y-chromosomal diversities. What was not known is if those diversities signal an area of origin which is totally in Africa. Additionally, there is disagreement regarding where in Africa the origin is. Considered in the present research was whether the expansion is suggested through various genetic diversities (including mitochondrial, X-chromosomal, and Y-chromosomal) and cranial traits (e.g., cranial size dimorphism), and where in Africa the expansion started. For each genetic or cranial variable, it was seen if the estimated area of origin was solely in Africa. To generally estimate where the expansion began in Africa, a centroid was calculated from potential origins that were obtained through indicators of the expansion. The area of origin was completely within Africa for each variable except one – for Y-chromosomal diversity, the area was possibly in Asia only. The centroid of the potential origins was in southern Africa. However, the support for a southern African origin (over elsewhere in Africa) could potentially reflect variation in non-African ancestry within Africa rather than the expansion. Nevertheless, a southern African origin was pointed to via the autosomal diversity of sub-Saharan African populations which had been adjusted for non-African ancestry. Southern Africa possible is the origin of the expansion.

Can behavior be unconsciously primed via the activation of attitudes, stereotypes, or other concepts? A number of studies have suggested that such priming effects can occur, and a prominent illustration is the claim that individuals' accuracy in answering general knowledge questions can be influenced by activating intelligence-related concepts such as professor or soccer hooligan. In 9 experiments with 475 participants we employed the procedures used in these studies, as well as a number of variants of those procedures, in an attempt to obtain this intelligence priming effect. None of the experiments obtained the effect, although financial incentives did boost performance. A Bayesian analysis reveals considerable evidential support for the null hypothesis. The results conform to the pattern typically obtained in word priming experiments in which priming is very narrow in its generalization and unconscious (subliminal) influences, if they occur at all, are extremely short-lived. We encourage others to explore the circumstances in which this phenomenon might be obtained.

Some diversities are thought to mark human expansion from Africa — they decline as distance from Africa accumulates, and suggest that the expansion originated from any of a range of locations which are only in Africa. Previously, a decline was found regarding Y-chromosomal microsatellite heterozygosity. However, this diversity has been noted to suggest a non-African starting point and, consequently, not appearing reflective of expansion from Africa. Declines have appeared in other variables derived through Y-chromosomal microsatellites, including effective population size, expansion time, and time to the most recent common ancestor. The present research inferred if these variables, and some Y-chromosomal diversities, indicate expansion from Africa; indicative variables could help with identifying which area of Africa the expansion started in. This research used variables derived previously from Y-chromosomal microsatellites for populations worldwide (effective population size, expansion time, and time to the most recent common ancestor) or only in Africa (haplotype and repeat unit diversities). Regarding populations worldwide, San were very high in each variable when considering distance from (southern) Africa. Without San, effective population size and time to the most recent common ancestor did not squarely indicate an African origin, and expansion time placed the origin wholly outside of Africa. When using San, each area was only in Africa. Amongst African populations, whilst both haplotype diversity and repeat unit diversity showed a geographical pattern of declining, only haplotype diversity suggested a completely African area of origin. Using Y-chromosomal haplotype diversity alongside some other genetic diversities, a southern African origin was broadly indicated.

Caucasian DPs and controls judged whether pairs of faces were identical or not • As expected, the DPs exhibited poor discrimination of same-ethnicity faces • Relative to controls, the DPs also exhibited impairment when judging Black faces • We found no evidence of disproportionate impairment for same-ethnicity faces • Both groups described similar levels of experience with other-ethnicity faces

Types of diversity have been known to decline linearly with the rise of geographical distance from Africa. Declines have helped to suggest the area in Africa which holds the origin for the global expansion of modern humans. Research has, at times, explored if there is a non-linear relationship between diversity and distance from Africa. A previous suggestion was that non-linearity could affect where the expansion appears to have originated. Linear analysis with Y-chromosomal microsatellite heterozygosity has been contrary to the expansion from Africa, instead indicating an origin involving Asia; could this be attributable to non-linearity? The present study looked into whether there are non-linear relationships between distance and diversities, and approximated where the expansion began. This study used diversities from previous research — genetic (autosomal, X-chromosomal, Y-chromosomal, and mitochondrial) and cranial shape. The Bayesian information criterion was the statistic for comparing linear and non-linear (quadratic) models to indicate if there is a non-linear relationship. This criterion was also used to estimate where the expansion launched from. Autosomal microsatellite heterozygosity favoured a non-linear relationship. This may be due to South American populations. Mitochondrial diversity suggested non-linearity too, but not when minimum temperature was controlled for. Whilst non-linear relationships indicated that the expansion had its start in Africa, for autosomal microsatellite heterozygosity, the area of origin appeared to be rather affected by the type of model (linear or non-linear). Other diversities (e.g., Y-chromosomal) supported linear relationships. Therefore, non-linearity does not seem to explain Y-chromosomal microsatellite heterozygosity being unexpressive of the global expansion.